A Savannah River Remediation employee monitors grout as it flows to a diversion box in Savannah River Site’s F Tank Farm.
A Savannah River Remediation employee monitors grout as it flows to a diversion box in Savannah River Site’s F Tank Farm.

AIKEN, S.C.EM and its liquid-waste contractor at the Savannah River Site (SRS) have filled two tank farm structures with cementitious grout to complete a significant step toward the operational closure of the first high-activity liquid waste facilities at the Savannah River Site (SRS) since 2016.

The structures, known as diversion boxes, are located in the site's F Tank Farm. The first box was filled in early November, while the second was completed on Jan. 18. The grout provides additional structural integrity to prevent possible collapse of the boxes, thereby ensuring long-term protection of workers, the public and the environment.

A diversion box is an underground concrete structure that contains a series of connection points that allow high-level radioactive waste to be transferred from one tank or facility to another. The two boxes filled with grout have been out of operation for more than 30 years. Both boxes met regulatory standards for closure, enabling the process to move forward.

In July 2021, EM and Savannah River Remediation (SRR) received final concurrence from the South Carolina Department of Health and Environmental Control and the U.S. Environmental Protection Agency that no additional waste removal from the two boxes was required. Concurrence was based on completion of all required federal and state regulatory documentation, a process that involved a public comment period as well as a public meeting.

SRR provided final documentation to EM in August 2021, demonstrating that all requirements needed to proceed with stabilization of the diversion boxes by filling them with grout had been met. In early October, SRR received final approval from the DOE Savannah River Operations Office agreeing that all requirements had been met and that SRR could proceed with stabilization.

On Oct. 26, the first of 11 truckloads of grout was poured into one of the diversion boxes. Over the course of four days, the structure was filled with 90 cubic yards of grout. When the filling of that box was complete, stabilization of the second box began. It was filled with 113 cubic yards of the material.

Jim Folk, the DOE-Savannah River assistant manager for waste disposition, said the grouting of diversion boxes is a significant step forward in the liquid-waste mission.

“Grouting of these structures reduces the risk to workers, the public, and the environment, and moves the liquid-waste mission forward,” said Folk.

SRR President and Project Manager Phil Breidenbach said he is pleased with his team’s progress.

“Grouting of these structures further reduces environmental risk onsite,” Breidenbach said. “Our closure team got the job done right and in accordance with our values, expectations and standards.”